Carroting process



Patented Feb. 21, 1939 PATENT OFFICE CARROTING PROCESS Warren G. Mercier, Danbury, Conn, assignor to American Hatters and Furriers Company, Incorporated, Danbury, Conn, a corporation of New York No Drawing. Application December 11, 1937, Serial No. 179,267

9 Claims.

This invention relates to a carroting process, an art of imparting proper felting characteristics to fur fibers.

This application is a continuation in part of my copending applications Serial No. 532,699, filed April 24, 1931 and Serial No. 104,707, filed October 8, 1936.

One of the objects of this invention is to provide a carroting process which will be instrumental in providing fur fibers having one or more of the following characteristicsz mutual affinity resulting in a'strong tight felt; an ability to felt ment during substantial periods of storage; an

ability to take all dye shades without objectionable undercasts'or other mottled effects; a satisfactory weight for economical use in hat manufacture. Another object of this invention is to provide a carroting process utilizing a non mercury carrot with a resulting economy and other advantages in hat manufacture. Other objects will be in part obvious and in part pointed out hereinafter.

The invention contemplates the utilization of novel combinations of chemical reagents for the treatment of furs as will be illustratively described herein, and the scope of the invention will be indicated in the following claims.

Briefly, felt, for example, the felt used in hat manufacture, comprises a compact mass of interlocking or interfitting fur fibers. In hat manufacture the fibers are deposited on a large cone in. matted down condition and by a wetting and hardening process they are made to cling together in mutual adherence to form a hat body much too large in size and of flimsy texture. Such bodies are carefully removed from the cone and subjected to a series of operations which reduce the hat to its normal size and at the same time cause a tight interlocking of the individual fibers to provide a strong felt. Such operations may be briefly described as shrinking, rubbing and pounding under a variety of conditions with many types of machines and naturally the greater the speed of such operations the greater the resultant economy in hat manufacture. Two of the most important operations are known as starting and sizing in the hatting industry. Fur fibers which are quick to start and fast in sizing are obviously desirable in hat manufacture.

Fur fibers in their natural state are unsuitable for the felting operation and must be processed prior thereto; this process is generally known in the art as carroting. Regardless of the quality of fur fibers, they are not suited for the felting operation unless the carroting process is carried out effectively 'prior thereto. This carroting process is usually accomplished by combing a chemical solution into the fur fibers before they are removed from the pelt. After this, the fur is dried and subsequently cut from the pelts When it is ready for the felting operation. In practice, however, carroted fur is generally stored for substantial periods of time and the process must be such that the fur will not deteriorate during this storage period.

Although several factors should be continually borne in mind to complete the carroting process in a successful manner, most important is the composition of the carroting solution. Such solutions should be free from toxic effects to protect laborers coming into contact therewith during the felting operation. Obviously the carroting solution should be inexpensive to reduce the ultimate cost of felt manufacture. As noted above, above, fur is often stored for substantial periods of time; therefore, the carroting composition should be free from any ingredients injurious to the fibers during such periods of storage. Felt is usually dyed, especially in the hatting industry and accordingly the carroted fur should be able to take all shades of dyes without undesirable "undercasting or mottled effects. So that the felting operation may be rapid, fur fibers should have quick starting and fast sizing characteristics.

Mercury carrot comprising mercury nitrate in an excess of nitric acid has been the accepted carroting composition in the hatting' industry for many years because of several desirable characteristics. Fur carroted with this mercury carrot may be stored for substantial periods of time for it improves with age and the mercury carrot adds a considerable amount of weight to the fibers. Fur carroted with the mercury carrot will also take a considerable amount of filler without affecting the quality of the resulting felt.. In spite of these advantages, fur carroted with the mercury carrot has a definite toxic effect which often seriously impairs the health of laborers coming in contact with the fur and it discolors the fur making it impossible to use light pastel dye shades on the resultant felt, thus often creating mottled effects even when the dark dyes are used.

Because the mercury carrot has these disad-' vantages several non-mercury carrots have been developed with limited success. Although such non-mercury carrots have proven practical in certain limited fields, they are all subject to one deficiency or another, making them unsuitable for universal use. Sometimes the fur does not take on enough weight when such carrots are used. With other nonmercury carrots the fur deteriorates during storage. Still other nonmercury carrots have slow starting and sizing characteristics. For these and other reasons the mercury carrot is still preponderantly used in hat manufacture in spite of the above-noted disadvantages thereof.

The principal object of this invention has been to provide an inexpensive and practical nonmercury carrot free from the disadvantages thereof noted above.

It is now generally recognized that a carroting solution should include a hydrolyzing agent and an oxidizing agent. The particular reasons why such ingredients are necessary constituents in a carroting solution are not definitely known but successful carroting solutions now in use include such ingredients in one form or another. A carroting solution comprising chloric acid and sulphuric acid has been suggested but after extensive research this carrot has proven a failure. One of the principal objections to this carroting solution is its slow starting and slow sizing characteristics, a disadvantage practically eliminating it for use in commercial operations. I have discovered that by the addition of certain peroxygen compounds to a solution of chloric and sulphuric acids, the above deficiencies thereof are successfully remedied and the result is an excellent carrot well adapted for commercial use.

My preferred carroting solution comprises a solution of chloric acid, sulphuric acid and ammonium persulphate. It is my belief that the chloric acid and the ammonium persulphate are the primary oxidizing agents and the sulphuric acid is a hydrolyzing agent. Under certain circumstances, I have obtained favorable results by substituting nitric acid for the sulphuric acid in this carrot so that the carrot comprises chloric acid, nitric acid and ammonium persulphate. Also, under certain conditions, I may substitute for the ammonium persulphate in this carroting solution hydrogen peroxide, potassium permanganate, ammonium perchlorate, and sodium perchlorate.

Thus, the solution or solutions used include a strong hydrolyzing agent and a pronounced oxidizing agent. Preferably I-employ two hydrolyzing agents, one at least of which is a strong hydrolyzing agent and a strong oxidizing agent. Preferably in one embodiment one of .the hydrolyzing agents is chloric acid, and if a second hydrolyzing agent is used I prefer to use sulphuric acid; the oxidizing agent may be hydrogen peroxide.

Accordingly, in summation, this carroting solution comprises chloric acid, nitric acid or sulphuric acid, and any one of ammonium persulphate, sodium perchlorate, ammonium perchlorate, hydrogen peroxide, or potassium permanganate. When hydrogen peroxide is used in this solution, the strength thereof should be some where between 25 and 50 volume.

Due to many factors to be taken into consideration when testing carroting solutions, I am unable at the present time to give exact values and proportions of the various ingredients comprising the above carroting solutions. However, my research has succeeded to such an extent that I have obtained satisfactory results with the solutions to follow, it being understood that these are merely illustrative examples and may vary widely in accordance with particular conditions:

Example 1 y M lal Chloric acid .4 Sulphuric acid .3 Potassium permanganate .15

Example 2 Molal Chloric acid I- .35 Sulphuric acid .3 Sodium perchlorate .8

Example 3 Molal Chloric acid .25 Sulphuric acid .2 Ammonium perchlorate .85

Example 4 Chloric acid molal .55 Sulphuric acid do .8 Hydrogen peroxide volume strength 50 Example 5 Molal Chloric acid .55 Sulphuric acid .8 Ammonium persulphate .8

Example 6 Mola Nitric acid .4 Chloric acid .6 Ammonium persulphate .7

These solutions are generally combed into th fur while it is still on the pelts and, after drying, the fur is cut from the pelts and used in the felting operation or stored. Fur so carroted may be used with absolute safety during the felting process without any toxic effects and the ingredients comprising the above solutions are relatively inexpensive; thus materially reducing the cost of the carroting process. This carroting solution adds considerable weight to the fur and may also be stored for substantial periods of time without deterioration. Furthermore, there is no discoloration of the fur and consequently the resultant felt may take any shades of dyes without undercasting or mottled efiects. Fur carroted with the above solutions will take a substantial quantity of filler without detracting from its felting characteristics and is also rapid in starting and shrinking.

Accordingly, I have accomplished the several objects hereinabove mentioned as well as many others in a practical manner.

As the art herein described may be varied in various parts without departing from the scope of the invention, it is to be understood that all matter hereinbefore set forth is to be interpreted as illustrative and not in a limiting sense.

I claim:

l. The herein described art of preparing fur for felting comprising applying to the fur a solution of chloric acid, sulphuric acid, and an oxidizing agent selected from the group consisting of ammonium persulphate, hydrogen peroxide, potassium permanganate, sodium perchlorate, and ammonium perchlorate.

2. The herein described art of preparing fur for felting comprising applying to the fur a solution of chloric acid, sulphuric acid, and ammonium persulphate.

3. The herein described art of preparing fur for felting comprising applying to the fur a solution of chloric acid, sulphuric acid, and sodium perchlorate.

4. The herein described art of preparing fur for felting comprising applying to the fur a solu tion of chloric acid .35 molal, sulphuric acid .3 molal, and sodium perchlorate .8 molal.

5. The herein described art of preparing fur for felting comprising applying to the fur a solution of chloric acid .55 molal, sulphuric acid .8 molal, and ammonium persulphate .8 molal.

6. The herein described art of preparing fur for felting comprising applying to the fur a solution of chloric acid, sulphuric acid and hydrogen peroxide.

7. The herein described art of preparing fur for felting comprising applying to the fur a solution of chloric acid and hydrogen peroxide.

8. The herein described art of preparing fur for felting comprising applying to the fur a solution of sulphuric acid and hydrogen peroxide.

9. The herein described art of preparing fur for felting comprising applying to the fur a solution of chloric acid .55 molal, sulphuric acid .8 molal, and hydrogen peroxide of 50 volume strength.

- WARREN C. MERCIER. 

